Combined air-intake and breather pipe



C. P. BROC'KWAY.

COMBINED AIR INTAKE AND BREATHER' PIPE.

APPLICATION FILED FEB. I4, 1919.

Patented. Apr. 25, 1922.

2 SHEETSSHEET Eql.

1 N VEN TOR.

C. P. BROCKWAY.

COMBINED AIR INTAKE AND BREATHER PIPE.

APPLICATION FILED FEB. 14, I919.

Patented Apr. 25 1922.

2 SHEETSSHEET 2,

I N V EN TOR. Carl 1? Brockwa l ATTORNEY cam. r. :enocxwAY, or renew, omo.

COMBINED AIR-INTAKE AND BREATHER PIPE.

Specification of LettersPatent. Patented Apr, 25, 1922.

Application filed February 14, 1919. Serial No. 276,952.

To all whom it may concern:

Be it known that I, CARL P. BROGKWAY, a citizen of the United States, residing at T- ledo, in the county of Lucas and State of Ohio, haveinvented certain new and useful Improvements in :Combined Air-Intake and Breather Pipes, of which I declare the following to be a full, clear, and exact description.

- for adding to the suction in the air cooling I cylinder engines.

means.

Other objects, and objects relating to details of construction and economies of manufacture will appear as I proceed with the description of that embodiment of the invention which, for purposes of the present application, I have illustrated in the accompanying drawings, in which:

Figure I is a view partly in transverse section of a gas engine embodying my invention.

Fig. II is a fragmental side elevational view looking toward the right in Fig. I. v

Fig. III is'a cross section taken on the line III-III, Fig. I.

Fig. IV is a cross section taken IV-IV, Fig. I.

F ig. V is a view principally in horizontal section on the line V-- V, Fig. II.

Similar reference characters refer to similar parts throughout the views.

For the purpose of illustrating my invention I have shown it in the drawings as applied to an air cooled, single cylinder gas engine of the sleeve valve type, 10 indicating the engine cylinder and 11 and 12 the valve on the line sleeves. The invention is equally applicable.v

to engines of other types however, and its utility is not necessarily confinedto single Consequently I do not wish the invention to be understood as limited in these respects. The piston 13 is driven by a connecting rod 14: from a crank shaft 15, which may carry counterweights 16 adapted to dip into the oil in an oil pan 17 for the purpose of lubricating the moving parts by the splash system.

The cylinder 10 is bolted to a crank case 18 made integral with the base 19 of the engine, which supports also outer walls 20 and 21 forming air chambers oneach side of the crank case. These chambers com municate through a series of openings 22 with a chamber .surrounding the cylinder, which latter chamber is formed by a cover 23 preferably of sheet metal having an end opening 24 for the admiss1on of air." Cooling air enters the opening 24, passes down around the cylinder into the chamber alongside the crank case, and thus into a combination flywheel and fan 25, from which the air is driven outwardly by centrifugal force.

A boss 26 cast integral with the engine cylinder is bored centrally to form a passage 27 leading to the intake valve28. To the face of the boss 26 there is secured, by means of machine screws or otherwise, a Venturi tube mixing chamber 29, which is cast integral with the air inlet pipe 30. The {latter at its lower end is turned inwardly and terminates in a fiat face adapted to be bolted to the fiat face of a boss 31 extending outwardly from the side wall 21. The boss 31 has a large opening 32 registering with the upper portion of the opening in the air inlet pipe 30 and a small opening 33, the bottom of which is'on a level with the bottom of the opening in the air inlet pipe. The opening 33 is a continuation of the opening in a breather pipe 34. leading from the crank case, the breather pipe being inclined downwardly towards the crank case in order that oil which may be condensed in the pipe 30 will fiowback into the crank case. A gasket 9 is inserted between the lower end of the pipe 30 and the face of the boss 31. In the drawings it is shown as provided with openings of .the same size as the openings 32 and 33, although obviously openings of lesser size may be used if desired. In this way it is possible to change the relative proportions of the two openings'32 and 33. 1 r

The amount of air entering the mixing chamber may be reduced at starting by pushing in a plunger 35, which carries a disc 36, thereby restricting the air passage and 39 formed in an integral extension of the tube. A valve stem 40' is threaded into the extension and may be adjusted by means of the knurled head 41 to regulate the flow of fuel into the Venturi tube. A preferred provision for priming consists of a small pocket 42 formed in a boss on the Venturi tube in the rear of the smallest part of its passage, which pocket is connected with theinterior of the Venturi tube, by a passage 43. It is desirable also to mount a strainer 44 in the pocket.

The operation of my invention is obvious from the above description of its construction. The flywheel fan 25 produces sufiicient suction through the chambers alongside the crank case and up through the openings 22 and chamber formed by the cover 23, all of which may be hereinafter referred to as an air cooling jacket, to produce a constant current of air downwardly through the opening 24 around-the cylinder and crank case and out through the fan, this keeping the engine from heating unduly. By the time the air has passed along the length of the cylinder and through the opening 22 it is warmed considerably, and it is this warm air which, in my construction, is taken into the air inlet pipe 30, thus assisting in the vaporization of the fuel. The suction of the air through the air inlet pipe, although only momentary, is quite strong as compared with that of the fan, and consequently adds something to the total suction downwardly through the chamber surrounding the cylinder. A further distinct advantage of my construction however, is that the noise made by the inrush of air is muffled because the inrush comes from a substantially closed chamber.

A breather pipe 34L acts. as a vent for the crank case, tending to relieve the pressure therein upon the descent of the engine piston. Because of the fact that its outer end is open to the air inlet pipe 30, it also tends to produce a slight vacuum in the crank case due to the suction of the engine and to the smaller suction caused by the fan, By means of such a vacuum- I. am able to counteract the tendency of the pressure impulses caused by the piston to force the Inbricating oil out of the bearings. The degree of vacuummay be controlled by changing the relative proportlons of the openin s 32 and 33.

The air in the crank case is laden with fine particles of oil, and also is mixed with gases which have leaked past the piston ring. A greater or less quantity of both oil and gas is carried up through the breather pipe 34 into the air intake pipe 30 and thus into the engine cylinder, where it is utilized, the oil assisting in the lubrication; of the cylinder. Whatever oil thus carried into the pipe 30 is caught upon the sides of the pipe finds its way back again through the breather pipe 34 into the crank case. 1

I am aware that the particular embodiment of my invention above described, and illustrated in the accompanying drawings, is susceptible of considerable variation without departing from the spirit thereof,

and therefore I desire to claim my invention broadly as well as specifically cated by the appended claims.

I claim as my invention:

1. The combination with an air cooled engine, of an air jacket surrounding said engine, an air intake for said engine, a connection between said air intake and the as indijacket below the base of the engine cylinthrough said casing and out through said chamber, and an air intake for the engine opening into said chamber.

3. In combination, a gas engine having a cylinder and crank case, a wall forming a chamber alongside said crank case, a casing surrounding said cylinder open at the ture.

CARL P. BROCKWAY. 

